Turbo power

[Voxonda]

According to SteveD I should open a new topic about my latest "brainwave", turbocharging one of my CB750 or in this case CB850.
My 'second' bike, the situp and beg one, will be treated with a Garrett T2 fed by a Mikuni HRS 42 carb.  Installation of the Turbo and other parts, like exhaust, oil feed and return will be done by myself. So that will be a challenge, since I know very little about Turbocharging. One thing I do know, that it is a effective way of filling the engine.
Will keep you posted.

Cheers, Rob

[peewee]

Hi Rob,
 I think the turbocharger is likely to fill your engine full of valves and pieces of moltern pistons,
 I'm no turbo expert but i think the compression needs to be lowered and a 'safe' rev limit set to avoid turning your Honda engine into a minature Blast furnace.Good luck with your venture and let us know how you get on
Cheers
Peewee
 

[Voxonda]

Hey peewee,

You've just shown me the down side of it all!! The cr will be lowered, but that depence a lot of how much 'boost' you're using. But it should/will be lowered to keep 'detonation' away. In the Garrett there's a boost-valve that opens if the boost is higher then preset. But I will be starting on the safe side to keep the engine in one piece.

Cheers, Rob

[Voxonda]

In order keep the CR somewhere around 8.5 :1, I will be using the conrods of our sister, the DOHC750. These are approx. 1.5 m/m shorter, big- and small-end are the same size. Bolts are a bid stronger and the rods themselves look a bit beefier. I think that is a more advanced solution then placing a spacer beneath the barrel.
Still waiting for the Mikuni and the Turbo to arrive. Then the real work can begin.

Cheers, Rob

[dave400]

Rob, sounds like you have a bit of reading and a lot of work ahead,  good luck with your new venture

[Voxonda]

Rob, sounds like you have a bit of reading and a lot of work ahead,  good luck with your new venture

[Voxonda]

This is the Mikuni:

[Voxonda]

The HD studs:

[Voxonda]

Of course, the Garrett T2:

[Voxonda]

The oil return:

[Voxonda]

And the difference in conrods:


Cheers, Rob

[peewee]

Hi rob sorry to take the mickey as you seem to know quite a lot about turbocharging theres an interesting site that i found at max-boost.co.uk
it goes into fueling lubrication etc
cheers and good luck
peter.

[Voxonda]

Hi rob sorry to take the mickey as you seem to know quite a lot about turbocharging theres an interesting site that i found at max-boost.co.uk
it goes into fueling lubrication etc
cheers and good luck
peter.

Hey Peter, thanks for that interesting site. All I really know about turbo's is from books and stuff, not from own experience yet. But after reading quite a bit about it, it's not really all that high tech. What I think is important, is what do you want to achieve? Just plain power, or a rideable bike for street use. I want a bit more power, more torgue and a bike that lasts. You can easily overdo things, with a lot of damage as a result.
Cheers, Rob

[SteveD CB500K0]

Do you read what was written in the 70's when people turbo'd Z1s. Even Kawi made the Z1R Turbo.

Keep the waste gate setting low and watch out for the killer turbo-lag!

[Voxonda]

Do you read what was written in the 70's when people turbo'd Z1s. Even Kawi made the Z1R Turbo.

Keep the waste gate setting low and watch out for the killer turbo-lag!

Hey steve, I know them stories! Wanted to own one myself back then, but couldn't get hold of one, back then, so ended up with a normally aspirated one.
I'll keep your advise in mind, I don't want to hurt myself!!!

Cheers, Rob